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By H W. Wu

The objective of this paper is to examine some modern forms of auxiliary ventilation fabric ducting with streamline design fittings and the efficiency of construction practices. The most dynamic form of auxiliary ventilation is a moveable fan and ducting, which is easy to install and uses light weight fabric. The porous nature of some ducting construction results in leakage and loss of efficiency. Flexible fabric ducting is primarily associated with metalliferous mining and industrial material quarrying. Some applications are found in coal in stone/rock development and with use of dust scrubbers.Forcing auxiliary ventilation systems employing circular fabric ducting have been examined. Leakage of air from ducting is affected by ducting material and construction methodology (such as welded or sewn), quality of installation, number of joints, total length, pressure differences between the inside and outside and diameter. The best ducting system with welded construction can have up to four times less leakage as compared with some systems with sewn construction. It is also evident that the sewn type ducting will deliver less air to working faces and require more fan power, hence higher operating costs to run when connected to the same fan.A case study has also been undertaken to compare predicted operating costs of auxiliary ventilation systems connecting various types of ventilation duct fittings. The study also assesses the technical importance of streamline design with low aerodynamic resistance to reduce the shock losses of the duct fittings. It was found that the system connected with streamline designed fittings is able to provide some power cost savings and deliver more air compared with the system fitted with conventional fitting pieces.Using a ventilation ducting system with a lower leakage and frictional characteristic represents a sound solution to new challenges faced by the industry for increasing demand for better quantities and quality of air delivered to working faces; this is due to higher production schedules and stricter mine health and safety regulations within the Australian mining industry.CITATION:Wu, H W and Gillies, A D S, 2017. A comparison of auxiliary ventilation systems and their predicted operational performances, in Proceedings Australian Mine Vent Conference 2017, pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By M Nagarajan

Orica Mining Services (Orica) in partnership with Coal and Allied’s Hunter Valley Operations (HVO) has developed a risk management process to maximise mining efficiency whilst controlling vibration and maintaining critical electricity continuity to New South Wales (NSW) electricity grid in the Riverview Pit. The issue is a high tension tower which supplies electricity located within 40 m of mining and blasting activities. The process involved developing an understanding of the relationship between vibration, explosives, geology and the location of the blasting in the geological horizon. From this an optimum methodology for blasting in each region was developed.

Nov 8, 2011

By H Bibby

Initial analysis of Long Offset Time Domain Electromagnetic (LOTEM) data has traditionally been made in terms of early and late time apparent resistivities. By using more than one grounded bipole as a source, a tensor analysis technique analogous to the method used to analyse DC resistivity multiple-source bipole-dipole surveying may be formulated. We define the æinstantaneous apparent resistivity tensorÆ as the tensor that relates the total electric field vectors at each instant to the steady state (DC) uniform half space current density vectors due to each source. Instantaneous apparent resistivity tensors calculated for a 3D resistivity model suggest that profiles of LOTEM measurements across simple 3D structures can be used to create an image that reproduces the main features of the subsurface resistivity. Where measurements are distributed over an area, maps of the tensor invariants or the tensor ellipses at different times can be made into a sequence of images which provide a way of ætime slicingÆ down through the target structure.

Jan 1, 1996

This article focuses on TurkeyÆs gold potential with respect to exploration, development and operation after 1985. Apart from TurkeyÆs geology, which offers a substantial number of volcanic-associated gold (Ag) and gold-copper (Au-Cu) projects, there are numerous other factors which make the country a favourable place for mining. Turkey has a mining history which goes back to pre-Roman times and an excellent mining code which ensures security for long-term production. In the country, the Government and local villagers are very positive and the country works extremely well logistically with excellent road and telecommunication links. The opportunities for new discoveries in Turkey are very high. Moreover, Turkey has its eyes turned west as it moves towards joining the European Community and it is no surprise that international companies believe it has got its timing as well as its partner relationship right. Newmont, Teck Cominco, BHP Billiton, Rio Tinto, Eldorado Gold, etc all have direct or indirect interests in Turkey, as do an increasing number of midtier and junior exploration companies. Turkish Koza Gold Mining is the first Au producing company of Turkey. The Eldorado Gold owned 245 t Kisladag Au deposit in Western Turkey is currently also producing Au. In the meantime Anatolia Minerals Development is advancing the 131 t resource at the C÷pler Au deposit in North Eastern Turkey. These are significant world-class deposits. Further encouragement for investment in the Au mining sector has been provided by the introduction of a new mining law in 1985. Foreign investments in the country were encouraged and have seen a rapid increase in the last two decades. Gross domestic product (GDP) growth is in excess of five per cent per annum, inflation is down from 70 per cent to single figures, the budget deficit has been cut by 40 per cent to 11 per cent and industrial output and productivity are increasing rapidly. Turkey is politically and economically stable, is a member of the European Customs Union, has a supportive mining legislation, is highly prospective and under-explored and hosts significant recent gold discoveries.

Jan 1, 2007

The increased focus on best practice environmental management has led to mining and mineral processing companies developing a variety of procedures to ensure that the environmental impacts of their operations are minimised, and that company managements are fully aware of these impacts and the policies and procedures established to ensure this process. Parallel to this, international standards for the development and implementation of environmental management systems are being promoted as necessary for companies to demonstrate their due diligence. Good environmental management systems should be built upon the systems already established within companies, and should ensure that the process of continual improvement is integral to their operation. An outline of the basic components of environmental management systems is provided, along with examples of the way various mining companies have implemented such systems. The benefits of best practice environmental management to mining companies are also considered.

Jan 1, 1995

By A Olshina, C Willman, D Moore

GeoScience Victoria has completed quantitative assessments of undiscovered gold endowment in the northern parts of the Bendigo and Stawell Zones. The under cover area in the Bendigo Zone (10 000 km2) is likely to contain approximately 1000 t and at least 290 t of gold in undiscovered mesozonal orogenic gold deposits. For the under cover area in the Stawell Zone (30 000 km2), the estimates are approximately 1200 t and at least 200 t of undiscovered mesozonal orogenic gold. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By J Shooter

Pezzimenti Laserbore designed, fabricated and commissioned the first microtunnelling machine in Australia in 1986. The System was initially a very basic one, developed in isolation to the overseas explosion in microtunnelling growth headed by Japan and Germany. Market needs in Australia have demanded increasing flexibility in microtunnelling capacity-longer distances, variable ground conditions and larger diameters. The one constant throughout the development process is in maintaining high accuracy û the attribute which most readily differentiates microtunnelling from other limited steering techniques.This paper will highlight the features of microtunnelling by drawing on case studies of completed projects.

Jan 1, 1999

Operation of the tankhouse at the Electro lytic Refining and Smelting Company's works has been improved, but further automation is re- quired to cut the labour intensive nature of the routine tasks. Anode quality, both chemical and physical, plays an important role in efficient refinery practice, and impurities such as lead, antimony and nickel have required careful monitoring for smooth operation. The gradual replacement of copper blanks by titanium has markedly improved the quality of starting sheets, but problems have been ex- perienced with surface preconditioning of the titanium blanks. Polishing with emery paper proved to be a successful technique.

Jan 1, 1976

The mining industry in common with the rest of Australian industry is in the critical situation of facing a rapidly diminishing insurance market. Huge industrial complexes and massive mining risks with limits of liability of millions upon millions of dollars are becoming increasingly difficult to insure. Insurance underwriters are still reeling from the financial shocks of cyclones, floods and fires in Australia over the past couple of years. Risk Management which calls for manage- ment involvement in the control of losses offers a serious challenge to miners, industrialists and insurance underwriters alike. Without it the insurance market could disappear altogether.

Jan 1, 1975

By Canterford JH

Current and future methods of data acquisition in hydrometallurgy are reviewed. Hydrometallurgical operations involve a wide range of chemical and physical processes for the recovery of metals and other products from ores and concentrates. Control of such operations requires information on the different liquid/solid and liquid/liquid mixtures being processed. Continuous. data acqui-sition for the liquid phases uses procedures already commercially exploited in other types of chemical plant. The major problem is the lack of robustness of measuring probes. Continuous analysis of the solid phases is much more difficult to-achieve because of the sampling and analytical techniques involved.

Jan 1, 1985

This paper suggests the models for determination the optimum life of machines on the basis of sum and difference of investment and maintenance costs. The economic-mathematical models are based on complex percentage method taking into account the time factor of referring cost. The following strategies of maintenance policy have been considered in machines repair: a strategy without investment, a strategy with continuous investment and a strategy with step-like investment. The effect of value of investment in repairing and time interval of investment on optimum machine exploitation life has also been considered. An illustrative example is presented.

Jan 1, 2003

By Aziz NI, Beafi EY

In designing for a highly productive new mine during the present declining coal market, a very detailed ò planning is necessary. Attitudes of both management and coal operators may have to be changed, with more initial participation by the unions, governmental agencies, and the coal owners. A considerable number of Australian mines are remote from labour source and this trend is likely to increase particularly in the state of Queensland. Consequently such 'mines must be developed on the basis of the future technological and social changes in order to minimise both the capital and operating costs.

Jan 1, 1988

By Roden S

This paper illustrates that sampling problems and difficulties are as common in an R&D environment as they are in an operating plant. Researchers need to be aware of the potential influence of poor sampling practices and when feasible determine the sampling and analytical precision at the start of any experimentation. Specific problems that have been encountered are discussed and the procedures implemented to overcome these difficulties are described. Examples from projects include the cyanidation of a Au/Ag ore, column leaching of refractory gold and oxide ores, the bioremediation of contaminated sites and the flotation of ore containing native copper.

Jan 1, 1976

Although most N.S.W. coal mines contain large amounts of combustible materials such as coal and timber, the introduction of mechanisation has extended the range of combustible materials now found underground. The role of combustible material in a fire is not clearly understood and as a result the assessment of these materials for flammability by small and large scale tests is doubtful. Extensive research has been carried out on the toxic and irritating gases evolved during the combustion of plastics. However, most autopsies report death due to carbon monoxide inhalation because the combined toxicity of smoke and fire gases is unknown.

Jan 1, 1981

The present practices in electro-refining of copper are shown to be the result of piecemeal and gradual improvements and innovations as metallurgists responded to changing cost pressures and the availability of new technology.Major changes were inhibited by capital cost restraints and a reluctance to build unproven ideas into new plants.It is suggested that the level of technology available today, combined with the greatest cost pressures the industry has known, call for fundamental re-appraisal and a questioning of widely accepted conventional practices.Examples of the industry reaction to changing pressures are given, and directions for future developments are suggested.

Jan 1, 1985

By Di Pasquale S, Osler GD

Mount Isa Mines Limited recently commiss ioned an 800 tph Heavy Medium Preconcentration Plant for lead/zinc/silver ores. The decision to build this plant was made in late 1979 based largely on investigations conducted in the Company's pilot plant on a variety of ore types including Hilton ores, between 1972 and 1978. The paper reviews the historical develop- ment of the pilot plant heavy medium circuit through this period and illustrates the extent to which this work impacted on the final design criteria. This review also includes a description of plant operation, manning levels, process equipment and metallurgical performance Achieved.

Jan 1, 1978

The exercise of preparing this paper has been both enjoyable and thought provoking.In carrying out the research I have spoken and written to many people. Without exception they have been eager to help, all have spoken of the high regard in which they held Dr Williams, not only as a metallurgist but also as a person.Review of GK's life reveals an enormous impact on the industry in which he worked and the people with whom he associated. Consideration of this impact inevitably leads to the question "what can we learn from his life and the way he went about his work?"

Jan 1, 1985

Modern mining and coal cleaning techniques lead to the generation of large quantities of fines which give rise to problems in their storage, handling, transportation and further processing. Pelletisation, a method of particle agglomeration, can alleviate such problems. This paper provides a brief overview of the principles of pelletisation and a survey of the coal pelletisation literature. Then it reports results from an experimental investigation of the effect of surface active reagents on coal pelletisation. Finally the paper is concluded with a few remarks on applying the results from the experimental study to practical coal agglomeration.

Jan 1, 2000

Organic dyes such as nigrosine and sun yellow act as depressants for carbonaceous particles in the, flotation of sulphide ores. Depression is achieved when initially hydrophobic organic surfaces are made hydrophilic by preferential adsorption of dye molecules. Experimental studies, mainly on Mount Isa ores, indicate that dyes are adsorbed as planar anionic micelles attached to carbonaceous surfaces by van der Waals and ion exchange attractive interactions. Relationships appear to exist between the amount of organic matter on the surface of ground particles, the surface area of the particles, the "saturation" adsorptions of dyes, and the degree of difficulty experienced during froth flotation.

Jan 1, 1975

By Ellicott C, Webb N

In November 1996 the NSW Minister for Mineral Resources, Hon Bob Martin MP, commissioned ACiL Economics and Policy Pty Ltd to conduct a wide ranging review of safety within the New South Wales mining industry.The review was a response to a disturbing number of fatalities which had occurred in the industry during the Minister's term of office together with a number of alarming near misses where serious failures in mining systems had occurred. Shortly after the review was commissioned, four mine workers died at Gretley Colliery near Newcastle. An inquiry is currently being conducted into the incident.

Jan 1, 1998